In the production of steel wool a plurality of steel wires are generally arranged in a band and passed in side-by-side respective grooves around a capstan adjacent a blade. This blade is positioned to cut shavings from the wire, these shavings being used to form the steel wool mats or pads. The wires typically have a starting diameter of up to 4 mm of which over 3 mm is reduced to shavings before the machine must be reloaded.
When round- or circular-section wire is used the first shavings are discontinuous and, therefore, unusable, and the subsequent shavings become ever thicker. Thus a certain amount of the metal is lost and a product of a very uneven quality is produced. Furthermore it is possible for the wire to twist in its own axis so that even once a substantial portion of the wire has been removed so that normally thick shavings could be made, the bad orientation will cause uneven shavings to be cut off.
In order to solve this problem it has been suggested to use square- or rectangular-section wire. The grooves in the capstan are correspondingly shaped so that an extremely sure and stable guiding of the wire is ensured. In addition relatively uniform shavings can be produced right from the start. A considerable disadvantage of this type of wire is, however, that there is considerable waste. Typically 14.2% of the wire cannot be used, compared to 9.6% in a circular-section wire.
In order to reduce this loss it has been suggested to combine the two sections by forming a wire whose upper portion is square or rectangular in section and whose lower portion, that is the portion guided in the capstan, is round. The grooves in the capstan are correspondingly formed round. Such an arrangement has, however, the disadvantage that the wires tend to twist in the capstan and, once again, shavings of nonuniform section are produced. Thus a low-quality steel wool is produced.